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authorHans de Goede2021-08-16 13:30:07 +0200
committerRafael J. Wysocki2021-08-16 18:32:02 +0200
commitb25d5a1cd19896bb87b399d6e24896cf6f854d44 (patch)
treeb334601a18f581fea190dad06855bb7c4aecb6ad /Documentation/ABI
parent7c60610d476766e128cc4284bb6349732cbd6606 (diff)
ACPI: platform-profile: call sysfs_notify() from platform_profile_store()
Drivers like thinkpad_acpi and ideapad_laptop call the platform_profile_notify() helper when the profile is changed by hardware (the embedded-controller/EC) in response to an EC handled hotkey. This allows userspace to monitor for such changes by polling for POLLPRI on the platform_profile sysfs file. But the profile can also be changed underneath a userspace program monitoring it by anonther userspace program storing a new value. Add a sysfs_notify() call to platform_profile_store(), so that userspace programs monitoring for changes also get notified in this case. Also update the documentation to document that POLLPRI polling can be used to watch for changes. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/ABI')
-rw-r--r--Documentation/ABI/testing/sysfs-platform_profile7
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-platform_profile b/Documentation/ABI/testing/sysfs-platform_profile
index dae9c8941905..baf1d125f9f8 100644
--- a/Documentation/ABI/testing/sysfs-platform_profile
+++ b/Documentation/ABI/testing/sysfs-platform_profile
@@ -26,3 +26,10 @@ Contact: Hans de Goede <hdegoede@redhat.com>
Description: Reading this file gives the current selected profile for this
device. Writing this file with one of the strings from
platform_profile_choices changes the profile to the new value.
+
+ This file can be monitored for changes by polling for POLLPRI,
+ POLLPRI will be signalled on any changes, independent of those
+ changes coming from a userspace write; or coming from another
+ source such as e.g. a hotkey triggered profile change handled
+ either directly by the embedded-controller or fully handled
+ inside the kernel.